In July and September 1909, Austrian neurologist Sigmund Freud and Swiss psychologist and psychiatrist Carl Jung presented a series of lectures on psychoanalytic theory at Clark University in Worcester, Massachusetts. Shown in this September 10, 1909, photo are, from left to right in the front row, Sigmund Freud, G. Stanley Hall, and Carl Jung, and from left to right in the back row, Abraham A. Brill, Ernest Jones, and Sándor Ferenczi.